1. Field of the Disclosure
The present disclosure relates to a control method for a bridging device and a bridging device using the method, and more particularly to a control method for a wireless sensor network (WSN) bridging device, a transmission flow balancing method, and a heterogeneous WSN bridging device using the method.
2. Related Art
A WSN is a network system formed by one or more wireless data collectors and a plurality of sensors, in which the communication among the elements adopts a wireless communication manner.
The potential applications of the WSN are quite wide, including, for example, military battlefield scouting, environmental pollution monitoring, weather information collection, health/medical nursing, traffic flow observation, and factory automation control.
In order to achieve an object of being widely constructed, the WSN needs to have low cost, low power consumption, and small volume, needs to be easily constructed, programmable, and dynamically formed, and needs to have an environment sensing devices, as well as other characteristics.
Considering the above characteristics, a technical standard named Zigbee is proposed in the industry to serve as a WSN communication protocol. The ZigBee is mainly proposed by the Institute of Electrical and Electronics Engineers (IEEE) 802.15.4 working group and ZigBee Alliance, which respectively formulate hardware standard and software standard. The ZigBee is a technique having a low transmission rate (from 20 kilo bits per second (kbps) to 250 kbps), a short distance (usually approximately from 50 m to 100 m, or reach 300 m depending upon different electric power consumptions), a low power consumption (usually approximately 1 milliwatts), and a simple architecture. Currently, the formulated frequency bands include global 2.4 GHz frequency band, 915 MHz frequency band in the US, and 868 MHz frequency band in European.
In another aspect, a ZigBee bridging device needs to have the Zigbee communication protocol and another communication network protocol, so as to transmit sensing information to a remote main control device. However, due to the difference in the data transmission bandwidths between two different heterogeneous networks, the bridging device disposed between the two different heterogeneous networks faces a bottleneck during the data transmission.
In addition, if the ZigBee and the wireless local area network (WLAN) are used at the same time, since the ZigBee and the WLAN both use 2.4 GHz frequency band, the signals of the ZigBee and the WLAN interfere each other when the ZigBee and the WLAN are actuated at the same time, thereby deteriorating the communication quality.